• BMB Reports
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• 제31권5호
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• pp.484-491
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• 1998

Acetylation of lysine residues within the aminoterminal domains of the core histones plays a critical role in chromatin assemhly as well as in regulation of gene expression. To study the biochemical function of histone acetylation, we have cloned a cDNA encoding the catalytic subunit of human histone acetyltransferase, Hat1. Analysis of the predicted amino acid sequence of human Hat1 revealed an open reading frame of 419 amino acids with a calculated molecular mass of 49.5 kDa and an isoelectric point of 5.5. The amino acid sequence of human Hat1 is homologous to those of known and putative Hat1 proteins from various species throughout the entire open reading frame. The recombinant human Hat1 protein expressed in bacteria possesses histone H4 acetyltransferase activity in vitro. Both RbAp46 and RbAp48, which participate in various processes of histone metabolism, enhance the histone acetyltransferase activity of the recombinant human Hat1, indicating that they are both able to functionally interact with the human Hat1 in vitro.

• 한국식품영양과학회지
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• 제42권10호
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• pp.1539-1543
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• 2013

본 연구에서는 Terminalia chebula Retz.의 성숙열매인 가자 메탄올 추출물(TCME)을 이용하여 HAT 활성을 억제함으로써 AR의 아세틸화 감소를 유도하여 전립선암세포의 성장을 억제하였다. TCME의 처리는 HAT 활성을 100 ${\mu}g/mL$의 농도에서 50% 이상 저해하였으며, p300과 CBP 등의 특이적 HAT 단백질에서도 유의적인 저해활성을 보였다. TCME를 0~100 ${\mu}g/mL$로 안드로젠 수용체 의존적 전립선 암세포인 LNCaP에 처리한 결과, reporter assay에서 AR 매개 전사를 억제하고 AR target gene의 mRNA 발현을 억제하였다. 동일 농도에서 AR의 아세틸화가 감소한 결과를 보였으며, 결국 전립선암세포주의 성장억제를 유도하였다. 이같은 결과에서 가자 메탄올 추출물은 HAT 활성을 억제하며, AR의 아세틸화를 감소시킴으로써 효과적인 전립선암 치료소재로 개발될 수 있는 가능성이 있음을 제안한다.

• Food Science and Biotechnology
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• 제16권3호
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• pp.457-462
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• 2007

Histone acetyltransferase (HAT) is a family of enzymes that regulate histone acetylation. Dysfunction of HAT plays a critical role in the development of cancer. Here we have screened the various plant extracts to find out the potent HAT inhibitors. The bellflower (Platycodon grandiflorum) root have exhibited approximately 30% of the inhibitory effects on HAT activity, especially p300 and CBP (CREB-binding protein) at the concentration of $100\;{\mu}g/mL$. The cell viability was decreased approximately 52% in LNCaP cell for 48 hr incubation. Furthermore, mRNA level of 3 androgen receptor target genes, PSA, NKX3.1, and TSC22 were decreased with bellflower root extract treatment ($100\;{\mu}g/mL$) in the presence of androgen. In ChIP assay, the acetylation of histone H3 and H4 in PSA promoter region was dramatically repressed by bellflower root treatment, but not TR target gene, Dl. Therefore, the potent HAT inhibitory effect of bellflower root led to the decreased transcription of AR target genes and prostate cancer cell growth with the repression of histone hyperacetylation.

• Asian-Australasian Journal of Animal Sciences
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• 제30권6호
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• pp.857-864
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• 2017

Objective: The purpose of this study was to investigate the influence of AMP-activated protein kinase (AMPK) activation on protein acetylation and glycolysis in postmortem muscle to better understand the mechanism by which AMPK regulates postmortem glycolysis and meat quality. Methods: A total of 32 mice were randomly assigned to four groups and intraperitoneally injected with 5-Aminoimidazole-4-carboxamide1-${\beta}$-D-ribofuranoside (AICAR, a specific activator of AMPK), AICAR and histone acetyltransferase inhibitor II, or AICAR, Trichostatin A (TSA, an inhibitor of histone deacetylase I and II) and Nicotinamide (NAM, an inhibitor of the Sirt family deacetylases). After mice were euthanized, the Longissimus dorsi muscle was collected at 0 h, 45 min, and 24 h postmortem. AMPK activity, protein acetylation and glycolysis in postmortem muscle were measured. Results: Activation of AMPK by AICAR significantly increased glycolysis in postmortem muscle. At the same time, it increased the total acetylated proteins in muscle 45 min postmortem. Inhibition of protein acetylation by histone acetyltransferase inhibitors reduced AMPK activation induced increase in the total acetylated proteins and glycolytic rate in muscle early postmortem, while histone deacetylase inhibitors further promoted protein acetylation and glycolysis. Several bands of proteins were detected to be differentially acetylated in muscle with different glycolytic rates. Conclusion: Protein acetylation plays an important regulatory role in postmortem glycolysis. As AMPK mediates the effects of pre-slaughter stress on postmortem glycolysis, protein acetylation is likely a mechanism by which antemortem stress influenced postmortem metabolism and meat quality though the exact mechanism is to be elucidated.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.184.1-184.1
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• 2003

HDAC and HAT (histone acetyltransferase) are involved in co-regulation in chromatin remodeling and the functional regulation of gene transcription. Abnormal recruitment of HDAC is related to carcinogenesis. Thus, the identification of potent histone deacetylase (HDAC) inhibitor has been considered as very intriguing approach for development for cancer chemotherapy. More recently, anti-inflammatory activity of SAHA cytokines was reported via reduction of proinflammatory cytokinres in vitro and in vivo. (omitted)

• 한국식품영양과학회지
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• 제46권2호
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• pp.169-176
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• 2017

본 연구에서는 쓴메밀 새싹 추출물(TBS)을 대상으로 histone acetyltransferase(HAT) 활성 저해능을 평가하고 oleic acid와 palmitic acid(OPA)를 이용하여 HepG2 세포에서 비알코올성 지방간을 유도하여 그 효과를 검토하였다. HeLa 세포의 nuclear extract(NE)를 HAT의 source로 하여 in vitro에서 TBS에 의한 HAT 활성 저해능을 평가한 결과 추출물의 처리에 의하여 HAT 활성이 억제됨을 관찰할 수 있었다. 또한, 대표적인 HAT 단백질인 p300과 CBP를 이용하여 동일한 방식으로 HAT 억제능을 평가한 결과 TBS 처리에 의하여 두 단백질 모두 활성이 감소하였으며, 특히 TBS는 p300의 활성을 특이적으로 저해함을 확인할 수 있었다. 그뿐만 아니라 HepG2 세포에 $400{\mu}M$의 oleic acid 및 $100{\mu}M$의 palmitic acid와 함께 $200{\mu}g/mL$, $500{\mu}g/mL$의 TBS를 처리한 후 NE를 이용하여 세포 내 HAT 활성을 측정한 결과 역시 추출물 처리에 의하여 세포 내 HAT 활성이 저해되어 있음이 관찰되었다. TBS에 의한 HAT 활성의 억제는 세포 내 다양한 단백질들의 아세틸화 저해와 지질축적에 의하여 아세틸화 변형을 일으키는 것으로 알려진 histone H3K9, H4K8의 아세틸화 및 H3K36의 아세틸화를 감소시켰으며, 세포 내 지질합성과 관련된 대표적 유전자인 SREBP1c, ACLY, FAS의 전사 활성 역시 저해함을 관찰하였다. 이와 같은 변화를 통하여 OPA에 의하여 HepG2 세포 내에 축적되었던 지질은 TBS의 처리에 의하여 효과적으로 감소하였으며 이때 처리된 OPA와 소재에 의한 세포 내 독성은 관찰되지 않았다. 그러므로 이러한 결과는 TBS에 의한 HAT 활성의 저해가 히스톤 단백질의 아세틸활 변형을 억제하고 이를 통하여 지방 합성 관련 유전자들의 전사 활성을 감소시켜 결과적으로 세포 내 지질축적을 방지하는 것으로 생각되며, TBS은 비알코올성 지방간질환의 예방에 좋은 천연물 소재로 활용될 수 있을 것이라 여겨진다.

• The Plant Pathology Journal
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• 제30권1호
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• pp.1-9
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• 2014

Acetylation of histone lysine residues occurs in different organisms ranging from yeast to plants and mammals for the regulation of diverse cellular processes. With the identification of enzymes that create or reverse this modification, our understanding on histone acetylation has expanded at an amazing pace during the last two decades. In fungal pathogens of plants, however, the importance of such modification has only just begun to be appreciated in the recent years and there is a dearth of information on how histone acetylation is implicated in fungal pathogenesis. This review covers the current status of research related to histone acetylation in plant pathogenic fungi and considers relevant findings in the interaction between fungal pathogens and host plants. We first describe the families of histone acetyltransferases and deacetylases. Then we provide the cases where histone acetylation was investigated in the context of fungal pathogenesis. Finally, future directions and perspectives in epigenetics of fungal pathogenesis are discussed.

• Biomolecules & Therapeutics
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• 제32권2호
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• pp.214-223
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• 2024

Metabolic abnormalities in the liver are closely associated with diverse metabolic diseases such as non-alcoholic fatty liver disease, type 2 diabetes, and obesity. The aim of this study was to evaluate the ameliorating effect of robinetin (RBN) on the significant pathogenic features of metabolic failure in the liver and to identify the underlying molecular mechanism. RBN significantly decreased triglyceride (TG) accumulation by downregulating lipogenesis-related transcription factors in AML-12 murine hepatocyte cell line. In addition, mice fed with Western diet (WD) containing 0.025% or 0.05% RBN showed reduced liver mass and lipid droplet size, as well as improved plasma insulin levels and homeostatic model assessment of insulin resistance (HOMA-IR) values. CD38 was identified as a target of RBN using the BioAssay database, and its expression was increased in OPA-treated AML-12 cells and liver tissues of WD-fed mice. Furthermore, RBN elicited these effects through its anti-histone acetyltransferase (HAT) activity. Computational simulation revealed that RBN can dock into the HAT domain pocket of p300, a histone acetyltransferase, which leads to the abrogation of its catalytic activity. Additionally, knock-down of p300 using siRNA reduced CD38 expression. The chromatin immunoprecipitation (ChIP) assay showed that p300 occupancy on the promoter region of CD38 was significantly decreased, and H3K9 acetylation levels were diminished in lipid-accumulated AML-12 cells treated with RBN. RBN improves the pathogenic features of metabolic failure by suppressing the p300-CD38 axis through its anti-HAT activity, which suggests that RBN can be used as a new phytoceutical candidate for preventing or improving this condition.

• Journal of Microbiology and Biotechnology
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• 제28권2호
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• pp.181-189
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• 2018

Candida albicans is a major pathogenic fungus in humans, and meets at first the innate immune cells, such as macrophages, in its host. One important strategy of the host cell to kill C. albicans is to produce reactive oxygen species (ROS) by the macrophages. In response to ROS produced by the macrophages, C. albicans operates its defense mechanisms against them by expressing its oxidative stress response genes. Although there have been many research studies explaining the specific transcription factors and the expression of the oxidative stress genes in C. albicans, the regulation of the oxidative stress genes by chromatin structure is little known. Epigenetic regulation by the chromatin structure is very important for the regulation of eukaryotic gene expression, including the chromatin structure dynamics by histone modifications. Among various histone modifications, histone acetylation is reported for its direct relationship to the regulation of gene expression. Recent studies reported that histone acetyltransferases regulate genes to respond to the oxidative stress in C. albicans. In this review, we introduce all histone acetyltransferases that C. albicans contains and some papers that explain how histone acetyltransferases participate in the oxidative stress response in C. albicans.

• Nutrition Research and Practice
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• 제13권3호
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• pp.196-204
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• 2019

BACKGROUND/OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is a common metabolic disease triggered by epigenetic alterations, including lysine acetylation at histone or non-histone proteins, affecting the stability or transcription of lipogenic genes. Although various natural dietary compounds have anti-lipogenic effects, their effects on the acetylation status and lipid metabolism in the liver have not been thoroughly investigated. MATERIALS/METHODS: Following oleic-palmitic acid (OPA)-induced lipid accumulation in HepG2 cells, the acetylation status of histone and non-histone proteins, HAT activity, and mRNA expression of representative lipogenic genes, including $PPAR{\gamma}$, SREBP-1c, ACLY, and FASN, were evaluated. Furthermore, correlations between lipid accumulation and HAT activity for 22 representative natural food extracts (NExs) were evaluated. RESULTS: Non-histone protein acetylation increased following OPA treatment and the acetylation of histones H3K9, H4K8, and H4K16 was accelerated, accompanied by an increase in HAT activity. OPA-induced increases in the mRNA expression of lipogenic genes were down-regulated by C-646, a p300/CBP-specific inhibitor. Finally, we detected a positive correlation between HAT activity and lipid accumulation (Pearson's correlation coefficient = 0.604) using 22 NExs. CONCLUSIONS: Our results suggest that NExs have novel applications as nutraceutical agents with HAT inhibitor activity for the prevention and treatment of NAFLD.